Tool holder



June 3o, 1942.

` E. M. LAUDERDALE TOOL HOLDER 2 Sheets-Sheet l Filed Oct. 2l, 1940 FIG; 4

June 30, 1942. l E. M. LAUDERDLE TOOL HOLDER Filed oct. 21, 1940 2 sheets-sheet 2 Patented June 30, 1942 UNITED STATES PAT-ENT VOFFICE TOOL HOLDER Earl lll. Lauderdale, Walnut Park, Calif. Y Appiicamoctober 21, 1940, serial Nn. 362,101

' 1s claims. (on. sz-s'i) mandrel from which it mayv be automatically My invention relates to tool holders, more particularly to devices for holding the various cutting, shaping or boring tools used in conjunction with lathes or similar machines, and among the objects of my invention are:

First, to provide a tool holder which increases the work output of a conventional lathe, particularly when used for production machining in which a quantity of identical work pieces are turned out.

Second, to provide a tool holderA which is adapted to hold interchangeably the various'tools `used to machine the work so that the operations may progress rapidly from one step to the next.

Third, to provide a tool holder in'which the machining tool is automatically aligned in an exact predetermined relation with the holder so that the proper positioning of each tool is assured; thus, it is merely necessary for the machinist to note the lathe setting of a given tool in order to replace the tool in the correct position for a given operationv on the workso that the same operation may be performed on a series of work pieces with assurance that the desired dimensions will be maintained.

Fourth; -to provide a tool holder that is equally drawn into the correct position.

Figure is an elevational view on reduced scale of the tool holder mandrel incorporated with a boring bar.

Figure 6 is a similar elevational view showing the tool holder mandrel incorporated with a drill chuck.

Figure 7 is van end elevational view of a modiiied form of tool holder mandrel which provides two positions of the cutting tool, the tool showing one position of the cutting tool.

Figure 8 is a similar end elevational view thereof showing the other ting tool.

Figure 8A is a plan View on a reduced scale' of the structure shown in Flgs. 'Z and 8 with the tool holder shank and key post in section.

adaptedto hold any of the diierent tools used in lathes such as conventional cutting or shaping tools, boring tools, vdrills or special machining y tools or jigs used for special machining operations.

Fifth, to provide a tool holder which affords a particularly rigid mounting for the machining tool, to minimize any vibration or chatter caused by the tool holderor machining tool.

Sixth, to provide a tool holder which incorporates 'a novel locking means which not only secures the parts of the tool holder against both vseparation or rotation, but also draws the parts together tightlyand rigidly, the lockingmeans. including aV cam of slight eccentricity so that Figure 3 is another sectional view taken` through 33 of Fig. 2.

Figure 4 is a sectional view of the. tool holder shank with the tool holder mandrel removed, but

Figure 9 is an 'end elevational view with a 'portion thereof in section of a further modied form of tool holder mandrel which provides three positions for the cutting tool.

Figure 9A isa plan view on a reduced scale of the structure shown in Fig. 9.

' Figure 10 is a sectional view thereof taken through the plane of the keyways.

The tool holden comprises generally, a tool holder shank l, a tool holder mandrel 2 and a key post 3.

The moiholqer shank is provided .with a stem of conventional formadapted to be secured in a conventional manner to the tool rest, not shown. of a lathe. At one end, the stem is provided with a head 5 which has a forward vertical side 6 disposed at an angle with respect to the axis of the stem and upper and lower sides l and 8 vat right angles to the forward side.

A horizontal, tapered bore 9 extends through the head, its larger end intersecting the forward side 6. -A cross bore I0 extends vertically fromA the upper to the lower sides of the head. Thev Vaxis of the cross bore is oiset laterally from the axis of the .tapered bore, but their peripheries intersect.

'I'he tapered bore 9 receives the tool holder mandrel 2 which is correspondingly tapered.

while the cross bore I0 receives the key post 3.

The mandrel 2 is provided with a keyway Il which is complementary to the cross bore I0, while the key post Iwhich is complementary to the tapered bore.

showing by dotted lines an initial position of the Thus, when the notch l2 is in registry with the taperedbore 9, the mandrel may be inserted or removed; and, when the keyway Il is in registry the key post may be rotated. l

position of the cutisprovided with a notch I2 'axis is offset approximately diametrically opposite from the notch I2 so that the low side I5a` of. the cam is provided with the notch. The highl side Ib of the camA is preferably tangential to the periphery of the bearing portions I3 andV I4.

The keyway II is slightly eccentric with respect to the axis of the cross bore and its center of curvature is located forwardly of the axis of the cross bore. The `radius 'of curvature of the keyway is equal to the radius of the cam portion and the axes of the keyway and cam portion substantially coincide when the ascending side I5c of the cam portion is rearward or toward the small end of the tapered bore.

To assemble the mandrel and tool holder shank, it is merely necessary to place the mandrel approximately in position; that is, the mandrel may be outwardly from its proper position as shown by vdotted lines in Fig. 4, or turned from its proper position as shown by dotted lines yin Fig. 2. The key post, as it turns from the position shown in Fig. 4 to that shown in Fig. 3, automatically aligns the mandrel. Once in position, the cam portion and rear wall of thekeyway coact to draw the mandrel tightly in place against both axial movement and rotation. The keyway and cam portion need have only superficial eccentricity and conseto receive a spring which assists `releasing the clamp element when the nut is loosened.

As shown in Fig. 5, the mandrel 2 may be provided with a boring bar 4I which extends coaxially therefrom and is provided at the end with a suitable tool holding means 42. Similarly, as shown in Fig. 6 a conventional drill chuck 5I may be provided with a mandrel 2.

Reference is now directed to Figures 7 andy 8. The construction here shown is a modied form of thetool holder mandrel in which two positions are provided for the cutting tool. While the double position mandrel may be formed by merely providing an added keyway, the mandrel diametrically opposite the keyway II, it is preferred to oiset the added keyway llaa few degrees from a one-hundred and eighty degree relation with the keyway II. This permits the cutting tool 32 having two cutting ends 32a and 3217A to have Van upwardly inclined position as shown in Fig. 7 or a horizontal position as shown in Fig. 8.

While the head of the mandrel may be identical to that shown in Figs. 1 and 3, a modified head 6I i`s illustrated. The head 6I is provided with a diametrically extending channel 62 which receives the cutting tool 32 and is relieved on one or both sides of the channel to form shoulders 63 through which set-screws 64 extend to secure modified head 1I is shown which is provided with quently only anominal torque need be applied to the key post to exert a strong holding force. Also, by placing the cam portion and notch of key post in the relative positions shown, the most effective section of the key post is placed in shear when the mandrel is tightened in place.

The key post is provided with a flange I8 and a wrench receiving means II at its upper end. Near its lower end the key post is provided with an annular groove I8 which is adapted to receive a set screw I9 secured in the head 5. A stop pin 20 is inserted in the-groove I8 to limit rotation of the key post.

The tool holder shankis secured semi-permanently to the tool rest of the lathe; `that is,'the shank remains secured to the tool rest while different mandrels each having incorporated'.-

. given to an ordinary lathe.

It is contemplated that each ofthe specinc tools used to perform a machine operation on a given piece of work has its individual integralA mandrel 2. Thus, as shown in Figs. 1 through 4, the mandrel is provided with a clamp element 3| which coacts with the forward face of the mandrel to hold a cutting tool 32. The clamp element is provided with aste'm33 which extends through a bore provided in the mandrel and receives a nut 34 for the purpose of tightening the clamp element against the mandrel. The manthree radiating channels I2 receiving cutting tools 'I3 which in this case are single ended. The head is relieved as indicated by I4 to provide shoulders 'I5 which receive set-screws 'It adapted to secure their respective cutting tools 13. As in the previously described structure additional keyways IIb and IIc are provided. The three channels 12 and their -corresponding keyways may be equally spaced or so positioned that some of the tools project horizontally and others are inclined when in operating position in the manner illustrated in Figs. 7 and 8.

While the holder herein described is primarily intended for use with lathes it should be noted that it may be used with other types of machine Though I have shown and described a particular embodiment of my invention, I do not wish to be limited thereto, but desire to include in the scope of my invention the constructions, combinations, and arrangements embraced in the appended claims.

I claim: i 1. A machining tool holder comprising: a

mounting member having a tapered socket therein, and a key bore disposed in laterally offset but intersecting relation therewith; a correspondingly tapered mandrel adapted to nt said socket and carrying a machining tool element; and a key post fitting said bore; said key post having .a notch complementary to said tapered socket -a head having a tapered bore and a laterally offset rightangularly disposed and intersecting cross bore; a tool carrying mandrel adapted to fit into said tapered bore and having a keyway adapted 'to register with said cross bore; and4 a drel bore may be counterbored at its forward end key post fitting said cross bore and including -removed by turning said :misano-iI cam means coacting with said keyway to draw the mandrel tightly into said tapered bore. l

3. A machining tool holder comprising: a mounting member adapted to be secured in the tool mounting means of a lathe; and including a head having a tapered bore anda laterally offset rightangularly disposed and intersecting cross bore; a tool carrying mandrel adapted to t into said tapered bore; and having a keyway.

adapted to register with said cross bore, and a.l

key post fitting said crossbore and having a recess complementary to said tapered bore to permit insertion of said mandrel, and including bore; a mandrel for said' tapered bore; a key post for said cross bore; said mandrel having a'lkeyway complementary to saidcross bore; said keyv post having a recess complementary to said tapered bore, and cam means incorporated in said l key post and having an operating face-inv the zone of said recess but arcuately disposed therefrom whereby, upon rotation of said key post,

said cam means engages said mandrel through A said keyway to urgesaid mandrel tightly into said tapered bore. t

10. A construction as set forth in claim 5 wherein'said key post-is provided with a recess 4complementary to said tapered bore in the zone of said cam portionwhereby, when said recessl l isv in registry with said tapered bore, said mandrel may be removed, said recess being located at the minor point of said cam portion whereby said recess is clear of said tapered bore when said cam portion is securing said mandrel.

11. A construction as set forth in claim l wherein the mandrel is proyided with a plurality said tapered bore, and having a keyway substantially complementary to said cross bore but disposed in superiicial eccentricity to said cross bore when said mandrel is in position; and a key post iitting said cross bore and including an eca centric cam portion adapted to coact with said a head having a tapered bore and a laterally` odset rightangularly disposed and intersecting cross bore; a tool carrying mandrel'adapt'ed to sidewall which is complementary to said tapered- A bore, whereby said mandrel may be inserted and removed by turning said recess into registry with said tapered bore.

7. A construction as set forth in claim 5 whereof keyways each complementary to said cross bore whereby said mandrel may be .adjusted in a plurality of positions. v

12. A machining tool holder comprising: a mounting member including a head portion having intersecting but offset tapered bore and cross bore; ,a mandrel for said tapered bore including a pair,of keyways-oiiset from diametrioally opposed positions, and means securing. a pair of cutting elements corresponding to said keyways and disposed in diametrically opposed relation; a key post for said cross bore, said key post having a recess complementary to said tapered bore; and cam means incorporated in said key post and having an operating face in the zone of said recess and engageable with the keyway oiy said mandrel in registry with said cross bore for urg'- ing said mandrel tightly into said tapered bore, said keyways being so related cutting elements that when coacting with said cam'means one key way positions its cutting element horizontally and the other its cutting ele-- ment on an incline.

13. A machining tool. holder comprising: a

mounting member adapted to be securedy in the in said key post is provided with a recess in its bore, whereby said mandrel may be inserted andE recess into registry withsaid tapered bore.

8. A machining tool holder comprising: a

mounting member including a head portion'having intersecting butoset tapered bore and cross bore; a. mandrel for said tapered bore; akey post'for said cross bore; said key post and` man-- drel having respectively a recess and ,a keyway complem tary to the other borefgd meansincorporate with said key 'post in the zone of its recess and, when said recess' is .out of registry with said tapered bore, engageable withl said mandrel through said keyway to urge said mandrel tightly into said bore.

a. A machining mp1 hoder .eomprismgz' s mounting member including ahead portion havl cross bore; a tool carrying mandrel adapted to -t'into saidtapered bore, and having a keyway substantially complementary to said cross bore when said mandrel is in position; and a key post having upper and lower journal portions fitting said bore and an intermediate cam portion of recess complementary to said tapered bore' inv -the zone of said cam portion whereby, when said recess is in registry with said tapered bore, said mandrel may be removed, said recess being located at the minor point of said cam portion lwhereby said recess is clear 'of said tapered bore whenv said cam portion .is securing said mandrel in said tapered-bore; said mandrel having a plu-v .v rality of keyways adapted to coact interchangeing intersecting but offset tapered boreand cross ably'with said key post; 'and a plurality of cutting means held by said mandrel 4and correspond. ing-to said keyways. y

1u. LAUDERDALE.

to their respective 

